Improvement in low-water indicators



TATES PATENT FFICE.

WILLIAM A. BRADFORD, OF CINCINNATI, OHIO.

IMPROVEMENT IN LOW-WATER INDICATORS.

Specification forming part of Letters Patent No. 113,843, datcd April 18, 1871.

To all whom it may concern:

Be it known that I, WILLIAM A. BRAD- FORD, of Cincinnati, Hamilton county, State of Ohio, have invented a certain new and useful Improvement in Low-Tater Indicators for Steam Boilers; and I hereby declare the following to be a sufficiently full, clear, and exact description thereof to enable one skilled in the art to which my invention appertains to make and use it, reference being had to the accompanying drawing, making part of this specification.

Nature and Objects of Invention.

My invention relates to the expansion-tube class of low-water indicators; and consists, iirst, in connecting the rod which, by the expansion of the tube, automatically opens the whistle-valve to the stem of the latter, by means of an intermediate adjustable thimble, in the socket of which said rod is fitted to' slide, so as to relieve the valve of all strain as the tube contracts, the valve being closed by a suitable spring; second, of an expansiontube centrally divided by a thin diaphragm, running` from the lowest point of the tube to near the upper end, for the purpose of causing a rapid displacement of the water by the steam when the water in the boiler falls bel'ow the proper level; third, in a peculiar form of diaphragm for the expansion-tube, by which it is rendered selffastening, fourth, in the employment, in connection with other parts, of a hand-lever for blowing the whistle independently of the action of the expansion-tube.

Description of thc Accompanying Drawing.

General Description. A is the expansion-tube, communicating i with the water-line of the boiler in the usual way. It is not surmounted by the whistle, the latter being always stationary, and communieating by a short channel, C, with the steamchamber of the boiler only, so that water cannot reach the valve of the Whistle at any time. The whistle l) is also located in so close proximity to the boiler, and so entirely separated from the expansion-tube, (which will contain at the top much colder water than that in the boiler,) that no condensation of steam can occur.

The valve E of my whistle is operated by the rod F and multil'ilying-lever G, the latter being jointed to the rod F and tube A at points H and I, and fulcrumed to the vertical rod J at K. The valve E is kept against the Vseat when the water in the boiler is at the proper height by the coiled spring L.

Into the upper end of the valve-rod an adjusting-thimble, M, is screwed, which receives vin the socket in its upper end the lower end of the rod F. This thimble is so adjusted in the valve stem that the end of the rod F sliding in its socket touches the bottom thereof when the expansion-tube is filled with heated water and the boiler is making steam.

By simply turning the thimble M the valve may be adjusted lto blow off at the desired point.

rIhe rod F, being connected to the adjustable thimble by a slip-joint, exerts no action on the valve as the expansion tube contracts on the cooling of the boiler, and the parts of the ap paratus are thus relieved of the excessive strain which must necessarily result where the said rod is pivoted to the valve-stem.

To the valve-stein a lever, N, is jointed, which is pivoted at O to the support J, and serves to enable the en ginecr to try the whistle at any time to test its condition.

A diaphragm, I), is fitted to the tube A, completely dividing into two parts for almost the entire length, a short distance at the top end being undivided. The diaphragm I? is formed in nearly the shape of the letter S to render it elastic, and thus enables it to be tightly forced into the tube A and made selfsustaining.

A, multiplying -lever G, rod F, and valve E,

the adjustable thimble M, for connecting the valve-stem and rod F, substantially'as and for the purpose set forth. Y

2. An expansion-tube for a 10W Water indicator, centrally divided by diaphragm P, as and for the purpose described.

3. The curved elastic selfsustaining dia,- phragm P, substantially as described.

4. In the described combination with the apparatus embodied in the rst clause of' claims, the Whistle-testing lever N, connected 

